Are you sure it is the weight and not that it is stiffness?

I've noticed that the more they hang over the edge of the bed the heavier they feel, it makes it hard to turn over or fluff to give your feet room.

I am sure you are not wasting your time - just do something quick in colors that your mother loves. I have found that Thermore (it is a polyester) is the lighest/thinnest batting I can find. They use it in quilted clothing and table runners a lot. I too am wondering if the dense quilting just made it hard for her to move the quilt around. I think I might make 2 quick tops, quilt one myself (loosely) using the Thermore batting and then sending the 2nd one to be tied.

second the thermore suggestion, love it's lightness, and hand quilts beautifully.
My mom is 89, and my late boss was 85. Both mention weight as reasons for no longer using things like sweaters, high thread count sheets, etc. neither would have a quilt on their bed, too heavy. Even the lightest ones.

The amount of quilting, and whether it's machine or hand quilting would not greatly affect the weight of a quilt, but it does change the density, so a heavily quilted quilt will feel heavier for its size. The quilting flattens the layers, forcing out the air, so the quilt takes up less space and is less buoyant. Tying a quilt instead of machine quilting it will make it seem lighter and easier to handle because it is less dense and incorporates more air. Does this make sense to anyone else?

How many spools of thread did you use to quilt it? Now, how much do those weigh. Even ON the spool you are talking about negligible ounces of weight from the quilting. However, the batting, and the piecing, as others have said, will play a major role. Also, the fabric itself. Some cotton is lighter weight than others. I made a lovely quilt with shot cotton and quilter's dream select batting. It is the lightest quilt I own, despite being a full size quilt.

And yes, I completely understand how a quilt can be too heavy for someone as they advance in age. My mother has several quilts I made - only one is light enough for her to manage now. I don't think you are wasting your time at all, especially if your sister uses a very lightweight batting.

Could it be all those small pieces and seams that added the weight?

I'm thrilled with this thread. One question, though. What exactly is "too heavy"? DH and I have had the too heavy conversation. Because I do not feel the sensation, I cannot really understand. Is too heavy a pain somewhere? Does it mean one cannot turn over easily? Is it something that aggravates a bad back? What is it? It seems it would help us to have a clearer idea of what is being meant so we can respond appropriately.

For me, bring on the heavy, snuggly, cozy, just like Gram who lived two blocks off Lake Michigan on the Wisconsin side made them quilts. Now how many can we get on the bed?

Pat

Some of my children complain about heavy quilts. Overall warm and natural batting is considered heavy. I was surprised to read the Hobbs 80/20 was as it is often one of the ones that comes to my mind to use as a lighter alternative. Some others I would suggest would be the Hobbs poly batting and Soft and Crafty Toasty 100 cotton. The Soft and Crafty has a nice drape but needs closer quilting. My own personal favorite is wool batting but it is not necessarily light or drape well.

That was my first thought, also. But try, poly batting and less seams as possible (simple pattern). Also sometimes, it's more mind than matter. If she thinks it is lighter with tying, tie.